This self-made millionaire and her fiancé never fight about money—here's their secret

When it comes to relationships, more money doesn't have to lead to more problems. Just ask Vivian Tu, a self-made millionaire and the founder of YourRichBFF.

Tu and her partner have been together for six years and never fight about money, she tells CNBC Make It.

"We have probably one serious fight every single year and not once has it been about money," she says.

A few strategies help them avoid arguments. For one, they discussed finances early on. "A month into our relationship, we laid it all out on the table," she says. "We were like, 'How much do you make? Show me your pay stub.'"

This helped them determine whether or not they had shared values about money and if their financial priorities aligned, Tu says.

As the relationship progressed, the now-engaged couple began using the "yours, mine and ours" system.

With this approach, Tu and her fiancé each have their own separate bank accounts, plus a joint account they both deposit into. They use the joint account to pay for their shared expenses, such as utility bills, mortgage payments and groceries, she says.

Since they know that they've allocated money toward covering their household needs first, neither person feels the need to monitor how the other spends the rest of their money.

"I have an account that I have money in, and I use that for things like going to get my lashes done or when I go out for dinner with girlfriends. And he has his own bank account that he uses when he has to pay the greens fees to go golfing or get a haircut," Tu says. "Neither of us have a problem with that."

Tu and her fiancé prefer this system over splitting expenses equally. "When you go 50/50 on every single thing, I think it leads to an unhealthy mentality," she says. "You're never always going to be giving perfectly 50."

That's not to say that you shouldn't split expenses at all, Tu says. You just shouldn't "nickel and dime" each other.

"When I go on Venmo and I see other couples Venmoing each other for light bulbs, I'm like, 'light bulbs are $8.' You don't need to Venmo your significant other for $4 for the light bulbs," she says. "That's excessive."

And at least once a month, Tu and her partner order a pizza and sit down together to discuss their expenses, investments and household costs. Once they're finished with that, they watch a movie. Turning budgeting into an enjoyable date night activity, she says, makes it feel less like a chore.

"Not only are you able to make it a little bit more romantic and fun," she says, "but you're also making sure that you're actually addressing your finances every single month."

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